Inhibitory effect of bone morphogenetic protein-7 on hepatic fibrosis in rats

Hepatic cirrhosis is a serious clinical problem caused by the accumulation of extracellular matrix, which can ultimately progress into hepatic failure. Transforming growth factor-beta1 (TGF-β1) plays a pivotal role in extracellular matrix production. Bone morphogenetic protein-7 (BMP-7), as a member of the TGF-β1 superfamily, has been well proved to be capable of reversing renal fibrosis in mice. In this study, we aim to investigate the potential effect of BMP-7 on hepatic fibrosis in rats.

Sprague-Dawley rats were randomly divided into five groups. In the hepatic fibrosis model group (n=8), rats was treated with porcine serum at 0.5 ml each time, twice a week. In the negative control group (n=10), rats were intraperitoneally injected with equal amount and frequency saline. Rats were injected with BMP-7 (100 μg/kg weight) before porcine serum intraperitoneal injection in the preventive group (n=9). For the early (n=10) and late (n=8) treatment group, rats were received with BMP-7 (100 μg/kg weight) every other day since the second and fourth week respectively after porcine serum injection. After eight weeks, the degree of liver fibrosis in rats was evaluated and the expression of TGF-β1 in liver tissues was detected by Western blot and immunohistochemistry.

The grade of hepatic fibrosis was significant attenuated by BMP-7 prevention and treatment compared with the rats in negative control group (P<0.05). In addition, the expression of TGF-β1 greatly decreased in the BMP-7 preventive and treatment groups detected by both Western blot and immunohistochemistry.

BMP-7 can attenuate and even prevent the level of hepatic fibrosis in rats through inhibiting the expression of TGF-β1 in the liver fibrotic tissues. Therefore, it may be a potential clinical drug for the prevention and treatment of hepatic fibrosis.